Process for the continuous finishing of knitted fabrics and hosiery goods

ABSTRACT

A PROCESS FOR FINISHING, ESPECIALLY BLEACHING AND/OR DESIZING KNITTED FABRICS AND HOSIERY GOODS, SUCH AS FOR EXAMPLE CELLULOSE FIBERS, WHEREIN THE KNITTED FABRICS AND HOSIERY GOODS ARE IMPREGNATED WITH THE TREATMENT LIQUOR, STEAMED, WASHED AND/OR RINSED AND DRIED. THE KNITTED FABRICS AND THE HOSIERY GOODS ARE CONTINUOUSLY TRANSPORTED AND GUIDED IN OPEN WIDTH AND WITHOUT ANY SUBSTANTIAL TENSION DURING THE INDIVIDUAL TREATMENT PROCESSES.

ll. 26, 1971 FLElSSNER 3,557,394

PROCESS FOR THE CONTINUOUS FINISHING 0F KNITTED FABRICS AND HOSIERY GOODS Filed Oct. 18, 1967 a I I lnventon "HA/Z FLe/SSME/Z United States Patent 3,557,394 PROCESS FOR THE CONTINUOUS FINISHING OF KNITTED FABRICS AND HOSIERY GOODS Heinz Fleissner, Egelsbach, near Frankfurt am Main, Germany, assignor to Vepa A.G. Filed Oct. 18, 1967, Ser. No. 677,503 Claims priority, application Germany, Oct. 18, 1966,

44 Int. 'Cl. B08b 3/00,- D06c 1/00 US. or. s-149.1

ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION The present invention relates to a process for the continuous finishing, especially bleaching and/or desizing of knitted fabrics and hosiery goods, particularly cellulose fibers such as for example cotton, wherein the knitted fabrics and hosiery goods are impregnated in the treatment liquor, steamed, washed and/or rinsed and dried.

The knitted fabrics and hosiery goods of cotton have been subjected to wet-finishing processes, for example desizing, kier-boiling, boiling-off, bleaching and optical brightening as well as dyeing in rope form. Treatment is effected discontinuously on a winch beck or in a treatment vat, whereby the material is exposed to the influence of the treatment medium for a sufficiently long time by letting it dwell in the respective treatment liquor. For woven fabrics which are substantially denser and accordingly less sensitive with respect to material guidance, continuuous processes and devices have already been suggested and used especially for dyeing and bleaching.

With knitted fabrics and hosiery goods the material guidance is extremely difiicult as these materials may not be subjected to tensile stress during the treatment, in order to retain the uniformity of the mesh structure. The uniformity of the mesh structure also leaves much to be desired in the case of a discontinuous treatment of the material in rope form, for example on a winch beck. Also the always more exacting requirements with respect to the levelness of the degree of whiteness, the absorbency and the improved control of the treatment processs can not be met with discontinuous treatments of the material in rope form. For a discontinuous treatment many operators are required which is of considerable consequence when considering the economics of the operation.

SUMMARY OF THE INVENTION An object of the present invention is to avoid the prior art disadvantage in processes for the finishing of knitted fabrics and hosiery goods.

Another object of the present invention is to provide an improved process for finishing knitted fabrics and hosiery goods and to improve the quality of the product.

A further object of the present invention is to provide an improved process for finishing, especially bleaching, dyeing and/or desizing knitted fabrics and hosiery goods continuously in open width.

Other objects and further scope of applicability of the present invention will become apparent from the detailed description given hereinafter; it should be understood,

Claims 7 ice however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modification within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

Pursuant to the present invention, it has been found that the above-mentioned disadvantages may be eliminated and a much improved process for the continuous finishing of knitted fabrics and hosiery goods can be obtained by transporting and guiding the tubes or lengths of knitted fabrics and hosiery goods in open width continuously and substantially without tension during the individual treatment processes and to expose said materials to the individual treatment media in this condition.

For impregnating the knitted fabrics and hosiery goods it is suggested to use a suction drum bowl and to remove excessive treatment liquid from the material by subsequently squeezing it or exposing it to vacuum extraction. The material which has been impregnated in this way can then be folded, steamed and Washed and dried while being guided on suction drums. Any other impregnating device which is suitable for knitted fabrics and hosiery goods may be employed as well.

According to another embodiment of the present invention it is suggested to subject cotton materials which are to be desized and bleached continuously to a desizing process, for example with sodium bromite and to a bleaching process, for example with a peroxide, without drying the material between these two treatment steps. Advantageously the washing process for desizing and bleaching is omitted. This can be accomplished by impregnating and steaming the cotton material first with the desizing liquor, 'by dehydrating the material as much as possible by squeezing and/or vacuum extraction, by impregnating the material with the bleaching liquor, by steaming, washing and/or neutralizing said material and finally by rinsing and drying the material. If necessary, the material may be finished in the last bowl before drying.

According to another feature of the present invention the present process is rendered more economical by applying the desizing and bleaching liquor simultaneously or in two steps, by permitting the material to dwell in a steam atmosphere and by subsequently washing and/or neutralizing, rinsing and drying the material.

According to a further embodiment of the present invention and for cotton materials which are to be desized and dyed it is suggested to carry out desizing and instead of the aforementioned bleaching treatment, the material is dyed with suitable dyestuffs, for example with indanthrene dyes in one single process. Here again, the treatment can be effected just like the combination desizing and bleaching process, that is either in one or in two bowls with a common steaming treatment or alternatively withone steaming treatment each for desizing and for dyeing.

For carrying out the aforementioned process an apparatus is provided which comprises a combination of the following individual units:

(a) A spreading device for the tubular material and/or the lengths of knitted fabrics and hosiery goods,

(b) At least one impregnating device, preferably a suction drum bowl with a squeezer or a vacuum extractor connected therebehind,

(c) A steamer, preferably a conveyor belt steamer, that is one which is provided with a conveyor belt as the conveyor means, which can be provided with a folding device arranged in the steaming chamber. The steamer can also be provided with sieve drums subjected to a suction draft as the conveying elements,

(d) Suction drum bowls for washing and possibly for finishing the material,

(e) A sieve drum dryer, preferably provided with a folding device at the discharge end of the apparatus,

(f) Conveying elements, especially conveyor belts disposed between the individual units for the tensionless transportation of the materials, especially wet materials, and

(g) A common regulating and/or control device for the aforementioned units.

If a belt steamer is used it is advantageous if the folding device is arranged in the steaming chamber and if a blower is correlated to the steam-permeable conveyor belt which passes the steam through the folded material. As a result of the steam penetration the material is heated up shock-like and very uniformly so that the material turnout is uniform and the steaming time is reduced. However, it is also possible to use a J-box as a steamer in which the material is stacked in a well known way in the long leg of the I-box and drawn out of the short leg of said box. If only short steaming times are required it is advantageous to use a sieve drum steamer with sieve drums subjected to a suction draft in order to obtain a good material guidance. It has been established by tests that for desizing, for example with sodium bromite, steaming times of about 15-20 seconds are generally sufficient. A good material guidance is obtained if lattice belts, especially wooden lattice belts are used as conveyor belts. However, in this case it is not possible to pass the conveyor belt through the squeezers but rather it is necessary to provide one conveyor belt each at both sides of the squeeze rollers.

If according to the present invention two treatment processes are combined, it is possible, depending on the process which has been chosen, to use the aforedescribed device essentially without modification if the desizing agent and the bleaching liquor and/or the dyeing liquor can be applied in one bowl. If the liquors are to be applied separately, two suction drum bowls are required instead of the one bowl. If the process requires a separate steam treatment, another impregnating device and another steaming device must be set up behind the first steamer. The other units remain essentially the same.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only and thus are not limitative of the present invention and wherein FIG. 1 is a schematic design of a continuous treatment apparatus for kinitted fabrics and hosiery goods; and

FIG. 2 is a cross-sectional view of the steamer of the apparatus according to FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawing wherein like reference numerals are used throughout the various views to designate like parts, the apparatus of the present invention comprises a tube or length of knitted fabric or hosiery goods 1 drawn out of a container 2 where it is stacked and passed via a spreading device 3 to a suction drum bowl 4 where it is impregnated with the treatment liquor. For dehydrating the material a squeezer 5 is correlated to suction drum bowl 4. The material 1 is then fed via an inclined lattice belt 6 to a steamer 7. The steamer is provided with an antechamber 8 subjected to a suction draft and with a water seal 14 by means of which a substantially air-free steam atmosphere is produced and maintained in the steamer. By means of a folding device 9 the material 1 is folded onto a steam-permeable conveyor belt 10. To the conveyor belt 10 a cross-current blower 11 is correlated with a heating device 12 for superheating the steam which is circulated by the cross-current blower 11. In one steam circulation cycle the steam is passed through the material twice. A heated sump 13 which is provided at the bottom of the steamer serves for the generation of saturated steam. However, the steamer may also be heated by means of live steam. For an easier unfolding of the material a trough 15 is correlated to the discharge end of the steamer. The material dropping into the trough is drawn off by means of a draw-off assembly 16 and passed on to suction drum bowls 17 for neutralizing and rinsing and possibly for the application of a finishing agent. To each suction drum bowl a squeezer 5 is correlated. For drying, a sieve drum dryer 18 with sieve drums 19 subjected to a suction draft is provided. Finally, the dried material is packed into a container 21 by means of a folding device 20.

If the steamer is used for dyestutf setting it is expedient not to fold the material but rather to handle it as a material length. For dyestutf setting a sieve drum steamer can be used with advantage. For the application of the treatment liquor a spraying device can be employed instead of a suction drum bowl.

The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scopeof the invention, and all such modifications are intended to be included within the scope of the following claims.

It is claimed:

1. A continuous process for treating knitted fabrics and hosiery goods in open width which comprises spreading the material, impregnating the material with a treatment liquor, folding the material in a spread-out state in slight undulations, steaming the impregnated and folded material for a period of time, said material being treated with superheated steam during the initial portion of the steaming stage of the process, washing the steam-treated material and drying the washed material, said material being conveyed substantially without tension during the various stages of the treatment process.

2. The process of claim 1 wherein the material to be treated is impregnated with the treatment liquor by using a suction drum bowl.

'3. The process of claim 2 wherein after impregnation the excess treatment liquor is removed from the material by squeezing said material or by vacuum extraction.

4. The process of claim 3 wherein the impregnated material is folded prior to being steamed.

5. The process of claim 4 wherein the material is washed and dried on suction drums.

6. The process of claim 1, wherein the knitted fabrics and hosiery goods are treated with a desizing liquor and a bleaching liquor.

7. The process of claim 1, wherein the knitted fabrics and hosiery goods are steamed for about 15 to 20 seconds.

8. The process of claim 1, wherein during the steaming stage of the process the knitted fabrics and hosiery goods are penetrated by the steam at least twice.

9. The process of claim 1, wherein the knitted fabrics and hosiery goods are folded in such a way that there is substantially no compression in the folds since said folds are not stacked against each other.

10. The process of claim 6 wherein the desizing liquor and the bleaching liquor is applied simultaneously before the steaming treatment.

11. The process of claim 6 wherein the desizing liquor and the bleaching liquor is applied separately before the steaming treatment.

12. The process of claim 6 wherein impregnation with a bleaching liquor is replaced with impregnation with a dyeing liquor.

13. The process of claim 12 wherein the dyeing liquor contains an auxiliary agent which prevents the precipitation of the starch products in the dyeing liquor.

14. The process of claim 12 wherein the desizing liquor and the dyeing liquor is applied simultaneously.

15. The process of claim 12 wherein the desizing 1iquor and the dyeing liquor is applied separately.

16. The process of claim 1 wherein the washing stage also includes neutralizing and rinsing.

17. The process of claim 1 wherein the knitted fabrics and hosiery goods are made of cellulose fibers, the desizing liquor is sodium bromite and the bleaching liquor is a peroxide.

18. A continuous process of desizing and bleaching cellulose fibers in open width which comprises spreading the fibers, impregnating the fibers with a desizing liquor, folding the material in a spread-out state in slight undulations, steaming said impregnated and folded fibers for a period of time, said material being treated with a superheated steam during the initial portion of the steaming stage of the process, dehydrating said fibers, impregnating the fibers with a bleaching liquor, steaming said impregnated fibers again, washing the steam-treated fibers and drying the Washed fibers, said fibers being conveyed substantially without tension during the various stages of the treatment process.

19. The process of claim 18 wherein the fibers are folded before the second steam-treatment stage,

3,263,458 8/1966 Cohn et a1. 6822 FOREIGN PATENTS 738,903 10/1955 Great Britain 8--l52 OTHER REFERENCES German printed application, No. 1, 134, 960, Aug. 23, 1962, Fleissner.

WILLIAM I. PRICE, Primary Examiner U.S. Cl. X.R. 1 -3 51 

